It would appear the theme object is unavailable in the app blocks/app embed framework.
I’ve tried simple things like outputting {{ theme.name }} {{ theme.id }} through to logic switching on
{% if theme.role == ‘unpublished’ %}
I’ve tried in app blocks which would be inserted in to the body and app blocks in the head but neither work.
Using the same code:
{% if theme.role == 'unpublished' %}
I'm unpublished
{% elsif theme.role == 'main' %}
I'm main
% endif %}
Works as expected when used in the liquid files in the code editor on an OS2.0 theme.